Complexity Factors Highlighting in PMBOK-Based Project Time

In the past two decades, using different methods and techniques for the implementation and management of construction projects has increased dramatically. Not only has the success rate of projects had appropriate progress, but also we have faced with schedule delays, increased costs, poor quality and increased number of claims and litigation. Nowadays major concern of many project managers is to complete the project on time and on budget in complex environment. Maybe we find out some environmental factors that impact on it, while the project managers do not consider that in critical situation. This research introduces the complex environment of construction projects and explains different types of complexity in order to achieve those factors. The main purpose of this paper is to identify complexity factors of project time management within the PMBOK process. In addition to proving complex and chaotic environment of project time management, we introduce these factors. Effective Parameters will be recognized and we should consider those in project planning and control, those are ignored in most of the projects and cause difficulty. Clarifying the problem and significant impacts on the implementation process will be represented the appropriate approach on project time management.